By Victoria Albert and Mariah Timms

President Trump's immigration crackdown is moving at a breakneck pace and is testing the limits of his administration's authority to quickly remove those it doesn't think should be in the country.

Here are the individuals whose cases could help define the scope of immigration enforcement:

Kilmar Abrego Garcia: What happens to someone wrongly deported?

The case of Kilmar Abrego Garcia raises a key question as the Trump administration carries out its fast-moving immigration policy: What happens when it makes a mistake?

The administration says that Abrego Garcia, a 29-year-old who had been living and working in Maryland, is a leader in the violent MS-13 gang and in March sent him with hundreds of others to a notorious prison in El Salvador. He had a legal work permit, but had entered the country without legal status as a teenager and hadn't been granted asylum. In 2019, an immigration judge ruled Abrego Garcia couldn't legally be sent to his home country because of a history of gang persecution against his family.

The administration insists it doesn't have the ability to initiate his return and that power rests with El Salvador's government. The judiciary has taken a dim view of that assertion, saying it flirts with violating court orders -- which sets up a looming clash of authorities.

A federal judge ordered that the government should immediately seek Abrego Garcia's return and the Supreme Court backed up her authority, but included language that she proceed with due deference to the president's powers over foreign affairs, which can be very broad. The judge has ordered expedited discovery in the coming weeks into whether the government is abiding by her order.

The case is likely to find its way back to the Supreme Court. If the government's gambit to deny custody of detainees such as Abrego Garcia once they are out of U.S. airspace is successful, it could consolidate power to carry out immigration enforcement with fewer checks by the courts.

Rumeysa Ozturk: Can the government decide where cases are heard?

The case of Rumeysa Ozturk, a Tufts University Ph.D. student, involves a series of rapid interstate custody transfers and a critical question about how much power the government has to decide in which jurisdiction such cases are decided.

Ozturk's lawyers filed a claim that her detention is unconstitutional in Massachusetts, where the Turkish student-visa holder was arrested. But by then, she had been taken through New Hampshire and into Vermont en route to Louisiana, where she is now detained.

People are generally required to challenge their detention in the district where they are being held. Ozturk's lawyers said they did everything they could to figure out where she was before filing and that the government transferred her to more places, over a much shorter period, than is typical. The government said because Ozturk's claim of unconstitutional detention was filed in the wrong jurisdiction, it would have to be dismissed or moved to Louisiana, which experts say is a less friendly venue.

The Massachusetts judge decided the case should be heard in Vermont because that is where Ozturk was at the time the case was filed. The government continued to push for Ozturk's claim to be dismissed on jurisdictional grounds.

A federal judge in Vermont on Friday said Ozturk must be returned to the state by May 1. "Ms. Ozturk has raised significant constitutional concerns with her arrest and detention which merit full and fair consideration in this forum," U.S. District Judge William K. Sessions III wrote.

The government's insistence the case be heard in Louisiana is unusual, said Kate Evans, a clinical professor of law at Duke University. Regardless of the outcome, legal experts say, the fight will still have delayed consideration of her larger claims.

Mahmoud Khalil: Do the government's broad foreign-policy powers outweigh the First Amendment?

Mahmoud Khalil, a 30-year-old Columbia University student, was arrested in New York City in early March as part of a crackdown on antisemitism on college campuses. His case sets up a novel clash between two fundamental principles: the First Amendment and the executive branch's authority to carry out foreign policy.

The Trump administration says it can deport Khalil, a green-card holder, under a rarely-used section of the Immigration and Nationality Act that allows it to remove a person it has a reasonable ground to believe is a foreign-policy threat.

The government hasn't provided specific evidence yet on how Khalil poses a foreign-policy risk, though it has cited his involvement with pro-Palestinian campus protests. Green card and student visa holders have free-speech protections, so his speech alone is likely an insufficient basis for deportation, said Jonathan Shaub, an associate professor at the University of Kentucky's law school.

"You've got an area in which the executive branch typically enjoys a lot of discretion, a lot of deference," said Shaub, who also worked in the White House Counsel's Office under then-President Biden. "But it's running headlong into bedrock First Amendment principles."

Y.S.M: What legal protections are people guaranteed before deportation?

Y.S.M. was born in Venezuela and entered the U.S. in 2022 as an unaccompanied minor to rejoin his father. The two applied for asylum, but their cases hadn't yet been heard when they were detained by immigration authorities in March. Officers this week attempted to pressure Y.S.M. to sign paperwork attesting to his gang membership but he refused, lawyers for the migrants said in court documents.

Y.S.M. is one of several individuals, identified in court documents only by initials, challenging their swift removals from the U.S. to a notorious prison in El Salvador, many under a wartime measure known as the Alien Enemies Act of 1798. These cases set up a fierce legal battle over what rights people have to challenge accusations against them before deportation.

Early Saturday morning, the U.S. Supreme Court temporarily blocked the Trump administration from using the wartime law to deport a group of Venezuelans. In a previous ruling, the court confirmed individuals designated as alien enemies are entitled to notice of pending removal from the country and an opportunity to challenge their deportations before a federal judge.

Write to Victoria Albert at victoria.albert@wsj.com and Mariah Timms at mariah.timms@wsj.com

(END) Dow Jones Newswires

April 20, 2025 05:00 ET (09:00 GMT)

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